From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 21 Aug 2025 00:14:22 +0000 (-0400)
Subject: __is_local_mountpoint(): use guards
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4151c3cc58698584e8b0427c40eeda671c3e08c6;p=users%2Fhch%2Fmisc.git

__is_local_mountpoint(): use guards

clean fit; namespace_shared due to iterating through ns->mounts.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/namespace.c b/fs/namespace.c
index 1ae1ab8815c9..f1460ddd1486 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -906,17 +906,14 @@ bool __is_local_mountpoint(const struct dentry *dentry)
 {
 	struct mnt_namespace *ns = current->nsproxy->mnt_ns;
 	struct mount *mnt, *n;
-	bool is_covered = false;
 
-	down_read(&namespace_sem);
-	rbtree_postorder_for_each_entry_safe(mnt, n, &ns->mounts, mnt_node) {
-		is_covered = (mnt->mnt_mountpoint == dentry);
-		if (is_covered)
-			break;
-	}
-	up_read(&namespace_sem);
+	guard(namespace_shared)();
+
+	rbtree_postorder_for_each_entry_safe(mnt, n, &ns->mounts, mnt_node)
+		if (mnt->mnt_mountpoint == dentry)
+			return true;
 
-	return is_covered;
+	return false;
 }
 
 struct pinned_mountpoint {